This invention relates to gas turbine engines and, more particularly, to a gas turbine engine having a variable fan nozzle for accommodating a foreign object strike event.
Gas turbine engines are widely known and used for power generation and vehicle (e.g., aircraft) propulsion. A typical gas turbine engine includes a fan section, a compression section, a combustion section, and a turbine section that utilize a primary airflow into the engine to generate power or propel the vehicle. The gas turbine engine is typically mounted within a housing, such as a nacelle. A bypass airflow flows through a passage between the housing and the engine and exits from the engine at an outlet.
Current regulations require that gas turbine engines meet a certain performance level following ingestion of a foreign object, such as a bird. Presently, engines are designed robustly to withstand such events and thereby meet a desired level. For example, the nacelle and fan of the fan section are made thicker or otherwise reinforced to withstand elevated stresses caused by the ingestion of the foreign object. Undesirably, this adds weight to the engine, which ultimately increases fuel consumption. Therefore, what is needed is an engine having enhanced controls for reducing the stresses caused from foreign object ingestion to thereby permit the nacelle and fan section to be less robust for improved fuel consumption. This invention addresses this need.